A bow sight can be used to assist an archer in aiming a bow. A typical bow sight includes a sight housing secured to the frame of a bow by one or more brackets. The sight housing often defines a viewing opening (i.e., a sight window) through which an archer can frame a target. The bow sight also typically includes at least one sighting member, such as a pin, that projects into the viewing opening. The sighting member defines and supports a sight point. The sight point is the point the archer aligns with the target during aiming. In use, the archer draws the drawstring of the bow and adjusts the position of the bow so that the intended target is visible through the viewing opening. While continuing to peer through the viewing opening with the bowstring drawn, the archer adjusts the position of the bow so that the sight point aligns with the intended target from the archer's eye. Once the sight point is aligned with the intended target, the archer releases the bowstring to shoot the arrow. “Target” herein can mean either a target being hunted or a fixed target. One example of a vertically adjustable sight is illustrated in U.S. Pat. No. 7,275,328.
The vertical position of one or more sight points is preferably set and calibrated to the user and bow so that each sight point position corresponds to a different target distance. Multiple sighting members are generally arranged in either a vertically aligned orientation, such as discussed in U.S. Pat. No. 6,418,633 or a horizontal orientation, such as discussed in U.S. Pat. No. 5,103,568. In certain embodiments, the sight points can be adjusted vertically to calibrate the sight points for differing target distances. Lower sight point positions typically correspond to longer target distances.
Adjustment of multiple sight pins for different distances often involves an archer, through trial and error, “sighting in” the bow at each distance so that each sight point position is accurately associated with a particular target distance. An alternate approach is to use computer software based on bow speed and other variables to prepare and print a sight tape which is then mounted on the bow sight and provides guidance for individually adjusting sight pins for various target distances. A still alternate approach, as discussed in U.S. Pat. No. 7,392,590, uses a multi-pitch lead screw to simultaneously adjust multiple sight pins.